/*--------------------------------------------------------------------------------------------------
Yatak Operation System Project Copyright 2012
Author : Ilya Churaev
Started : 20 Apr 2012		Updated : 29 Jun 2012
File Name : idt.c			Purpose : install new IDT
--------------------------------------------------------------------------------------------------*/
#include <yatak/debug.h>
#include <yatak/port.h>
#include <yatak/idt.h>
#include <yatak/gdt.h>
#include <yatak/isr.h>
#include <screen.h>

// Lets us access our ASM functions from our C code.
extern void idt_flush(uint32);

// Internal function prototypes.
static void idt_set_gate(uint8,uint32,uint16,uint8);

idt_entry_t idt_entries[256];
idt_ptr_t   idt_ptr;

// Extern the ISR handler array so we can nullify them on startup.
extern isr_t interrupt_handlers[];

void init_idt()
{
	idt_ptr.limit = sizeof(idt_entry_t) * 256 -1;
	idt_ptr.base  = (uint32)&idt_entries;
	
	memset(&idt_entries, 0, sizeof(idt_entry_t)*256);
	
	// Remap the irq table.
	dprintf ("[init_idt] Remap the irq table...\n");
	outportb(0x20, 0x11);
	outportb(0xA0, 0x11);
	outportb(0x21, 0x20);
	outportb(0xA1, 0x28);
	outportb(0x21, 0x04);
	outportb(0xA1, 0x02);
	outportb(0x21, 0x01);
	outportb(0xA1, 0x01);
	outportb(0x21, 0x0);
	outportb(0xA1, 0x0);
	
	dprintf ("[init_idt] Install interrupt descriptors...\n");
	idt_set_gate( 0, (uint32)isr0 , 0x08, 0x8E);
	idt_set_gate( 1, (uint32)isr1 , 0x08, 0x8E);
	idt_set_gate( 2, (uint32)isr2 , 0x08, 0x8E);
	idt_set_gate( 3, (uint32)isr3 , 0x08, 0x8E);
	idt_set_gate( 4, (uint32)isr4 , 0x08, 0x8E);
	idt_set_gate( 5, (uint32)isr5 , 0x08, 0x8E);
	idt_set_gate( 6, (uint32)isr6 , 0x08, 0x8E);
	idt_set_gate( 7, (uint32)isr7 , 0x08, 0x8E);
	idt_set_gate( 8, (uint32)isr8 , 0x08, 0x8E);
	idt_set_gate( 9, (uint32)isr9 , 0x08, 0x8E);
	idt_set_gate(10, (uint32)isr10, 0x08, 0x8E);
	idt_set_gate(11, (uint32)isr11, 0x08, 0x8E);
	idt_set_gate(12, (uint32)isr12, 0x08, 0x8E);
	idt_set_gate(13, (uint32)isr13, 0x08, 0x8E);
	idt_set_gate(14, (uint32)isr14, 0x08, 0x8E);
	idt_set_gate(15, (uint32)isr15, 0x08, 0x8E);
	idt_set_gate(16, (uint32)isr16, 0x08, 0x8E);
	idt_set_gate(17, (uint32)isr17, 0x08, 0x8E);
	idt_set_gate(18, (uint32)isr18, 0x08, 0x8E);
	idt_set_gate(19, (uint32)isr19, 0x08, 0x8E);
	idt_set_gate(20, (uint32)isr20, 0x08, 0x8E);
	idt_set_gate(21, (uint32)isr21, 0x08, 0x8E);
	idt_set_gate(22, (uint32)isr22, 0x08, 0x8E);
	idt_set_gate(23, (uint32)isr23, 0x08, 0x8E);
	idt_set_gate(24, (uint32)isr24, 0x08, 0x8E);
	idt_set_gate(25, (uint32)isr25, 0x08, 0x8E);
	idt_set_gate(26, (uint32)isr26, 0x08, 0x8E);
	idt_set_gate(27, (uint32)isr27, 0x08, 0x8E);
	idt_set_gate(28, (uint32)isr28, 0x08, 0x8E);
	idt_set_gate(29, (uint32)isr29, 0x08, 0x8E);
	idt_set_gate(30, (uint32)isr30, 0x08, 0x8E);
	idt_set_gate(31, (uint32)isr31, 0x08, 0x8E);
	idt_set_gate(32, (uint32)irq0, 0x08, 0x8E);
	idt_set_gate(33, (uint32)irq1, 0x08, 0x8E);
 	idt_set_gate(34, (uint32)irq2, 0x08, 0x8E);
	idt_set_gate(35, (uint32)irq3, 0x08, 0x8E);
	idt_set_gate(36, (uint32)irq4, 0x08, 0x8E);
	idt_set_gate(37, (uint32)irq5, 0x08, 0x8E);
	idt_set_gate(38, (uint32)irq6, 0x08, 0x8E);
	idt_set_gate(39, (uint32)irq7, 0x08, 0x8E);
	idt_set_gate(40, (uint32)irq8, 0x08, 0x8E);
	idt_set_gate(41, (uint32)irq9, 0x08, 0x8E);
	idt_set_gate(42, (uint32)irq10, 0x08, 0x8E);
	idt_set_gate(43, (uint32)irq11, 0x08, 0x8E);
	idt_set_gate(44, (uint32)irq12, 0x08, 0x8E);
	idt_set_gate(45, (uint32)irq13, 0x08, 0x8E);
 	idt_set_gate(46, (uint32)irq14, 0x08, 0x8E);
	idt_set_gate(47, (uint32)irq15, 0x08, 0x8E);
	
	idt_set_gate(105, (uint32)isr105, 0x08, 0x8E);
	idt_set_gate(85, (uint32)isr85, 0x08, 0x8E);
	
	idt_flush((uint32)&idt_ptr);
	
	MessageFoS ("Initialising IDT\t\t\t\t\t\t", true);
}

static void idt_set_gate(uint8 num, uint32 base, uint16 sel, uint8 flags)
{
	idt_entries[num].base_lo = base & 0xFFFF;
	idt_entries[num].base_hi = (base >> 16) & 0xFFFF;
	idt_entries[num].sel     = sel;
	idt_entries[num].always0 = 0;
	// We must uncomment the OR below when we get to using user-mode.
	// It sets the interrupt gate's privilege level to 3.
	idt_entries[num].flags   = flags  | 0x60;
}
